I still haven't found out what's new with this version, but it's very possible that it may have messed your pidgin install: one of the updated libraries from collabora repository is libpurple, which is used by Pidgin.... And it looks like Pidgin is also distributed by Collabora, so maybe it overwrote your install of Pidgin from another source? (I really don't know how AppManager manages these situations, but I suspect that it will try to install the latest version it finds, even if it comes from another source?)